NL2014541B1 - Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for. - Google Patents

Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for. Download PDF

Info

Publication number
NL2014541B1
NL2014541B1 NL2014541A NL2014541A NL2014541B1 NL 2014541 B1 NL2014541 B1 NL 2014541B1 NL 2014541 A NL2014541 A NL 2014541A NL 2014541 A NL2014541 A NL 2014541A NL 2014541 B1 NL2014541 B1 NL 2014541B1
Authority
NL
Netherlands
Prior art keywords
bipolar membrane
fluids
energy
difference
contact
Prior art date
Application number
NL2014541A
Other languages
Dutch (nl)
Other versions
NL2014541A (en
Inventor
Saakes Machiel
Victor Marie Hamelers Hubertus
Johannes Van Egmond Willem
Original Assignee
W&F Beheer B V
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to NL2014541A priority Critical patent/NL2014541B1/en
Application filed by W&F Beheer B V filed Critical W&F Beheer B V
Priority to US15/556,887 priority patent/US10541439B2/en
Priority to PCT/NL2016/050207 priority patent/WO2016159761A1/en
Priority to DK16727238.4T priority patent/DK3274078T3/en
Priority to KR1020177030313A priority patent/KR102526924B1/en
Priority to EP16727238.4A priority patent/EP3274078B1/en
Priority to ES16727238T priority patent/ES2738413T3/en
Priority to CN201680019106.3A priority patent/CN107873111B/en
Publication of NL2014541A publication Critical patent/NL2014541A/en
Application granted granted Critical
Publication of NL2014541B1 publication Critical patent/NL2014541B1/en
Priority to HK18108463.1A priority patent/HK1248923A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04746—Pressure; Flow
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/18—Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
    • H01M8/184—Regeneration by electrochemical means
    • H01M8/186—Regeneration by electrochemical means by electrolytic decomposition of the electrolytic solution or the formed water product
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/18—Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
    • H01M8/184—Regeneration by electrochemical means
    • H01M8/188—Regeneration by electrochemical means by recharging of redox couples containing fluids; Redox flow type batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/22—Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen
    • H01M8/227—Dialytic cells or batteries; Reverse electrodialysis cells or batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
    • H01M8/2455—Grouping of fuel cells, e.g. stacking of fuel cells with liquid, solid or electrolyte-charged reactants
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2250/00—Fuel cells for particular applications; Specific features of fuel cell system
    • H01M2250/10—Fuel cells in stationary systems, e.g. emergency power source in plant
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02B90/10—Applications of fuel cells in buildings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

The invention relates to a method for operating a regenerative bipolar membrane fuel cell and regenerative bipolar cell for storing and generating energy. The method according to the invention comprises: providing a regenerative bipolar membrane fuel cell comprising: a reactor with an anode compartment having an anode and a cathode compartment having a cathode; and a number of cell units separating the anode and cathode compartments, wherein the cell unit comprises an anion exchange membrane, a cation exchange membrane, and a bipolar, with the membranes defining compartments; providing a fluid on both sides of the bipolar membrane with ion concentrations such that water activity difference between the fluids on both sides of the bipolar membrane is minimized; storing energy in an energy storage state by providing an external current to the reactor such that a pH difference between fluids in contact with the bipolar membrane is achieved; switching between the energy storage state and an energy generation state; and regenerating energy in the energy generating state from the pH difference between fluids in contact with the bipolar membrane.

Description

Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for
The present invention relates to a method for operating of a regenerative bipolar membrane fuel cell capable of storing and generating energy. This enables energy storage in a time period of an energy surplus and using this energy in a time period of energy shortage. Temporarily storage of energy is important to match supply and demand of energy, and for peak shaving of the energy demand. For example, this enables energy storage supplied by solar energy, wind energy, water energy etc.
Conventional energy storage devices include batteries that do not provide a sustainable approach on the long term due to the decreased reserves of many important elements needed for battery production.
Conventional energy generating methods may involve performing a reversed electro-dialyses process (RED) as described in WO 2007/094659 using differences in electrolyte solutions. Such differences are present between sea water and river water, for example. Such RED process can also be used to neutralize acidic and caustic effluent waste streams, such as in the semiconductor industry, and generating energy while these waste streams are treated. For example, US 2013/0288142 discloses such waste stream treatment process with a RED system comprising a bipolar membrane.
Conventional methods and devices are confronted with the problem how to regenerative store and generate energy in order to match energy supply and energy demand in an effective manner.
The present invention has for its object to provide a method for operating of a regenerative bipolar membrane fuel cell configured for storing and generating energy and capable of energy storage in time periods of energy surplus and energy discharge in time periods of energy shortage in an effective manner.
This objective is achieved with the method for operating of a regenerative bipolar membrane fuel cell according to the present invention, wherein the method comprises the steps of: providing a regenerative bipolar membrane fuel cell comprising: a reactor with an anode compartment having an anode and a cathode compartment having a cathode; and a number of cell units separating the anode and cathode compartments, wherein the cell unit comprises an anion exchange membrane, a cation exchange membrane, and a bipolar membrane, with the membranes defining compartments; providing a fluid on both sides of the bipolar membrane with ion concentrations such that water activity difference between the fluids on both sides of the bipolar membrane is minimized; storing energy in an energy storage state by providing an external current to the reactor such that a pH difference between fluids in contact with the bipolar membrane is achieved; switching between the energy storage state and an energy generation state; and regenerating energy in the energy generating state from the pH difference between the fluids in contact with the bipolar membrane.
Providing a regenerative bipolar membrane fuel cell enables storing of electrical energy using a system comprising a cation exchange membrane, a bipolar membrane and an anion exchange membrane. Between the membranes compartments are defined. The system is also capable of generating electrical energy with the same membrane configuration. This obviates the need for using different membrane configurations in the different states or operations of the system according to the invention. This provides an effective method for regenerative storing and generating energy.
In an energy storage state, an external current is supplied to the reactor. More specifically, the current is supplied such that a concentration gradient, involving a pH difference, between the anode and cathode compartments is achieved. This involves performing an electrodialysis (ED) process. Such electro-dialyses process is for example described in WO 2007/094659 and involves applying a voltage between the anode and cathode such that positive ions will be inclined to move to the cathode, while the negative ions will be inclined to move to the anode. Due to the use of ion exchange membranes, the actual feed flows through a compartment will change in (alternating) concentrated and diluted electrolyte solutions.
According to the invention, in the energy storage state, providing an external current achieves that the concentration of the fluids in contact with the bipolar membrane increase. Preferably, these fluids are an acid fluid and a base fluid. This achieves a pH difference between the fluids that are in contact with the bipolar membrane on different sides thereof. In a presently preferred embodiment of the invention the concentration of the third solution, a salt solution, decreases.
When energy demand is higher than the energy supply, the system can be switched from the energy storage state to the energy generation state such that energy can be (re)generated from the concentration gradient. This involves performing a reverse electrodialysis (RED) process which is also described in WO 2007/094659. Due to the concentration differences between the concentrated and diluted electrolyte solutions, ions will be inclined to move from the high to the low concentrations. Due to membranes limiting freedom of movement of the ions, there will be nett transport of cations and anions in opposite directions such that to maintain electric neutrality at the anode and cathode, reactions take place such that electrons may flow from the anode to the cathode, thereby creating an electric current.
According to the invention, in the energy generation state, the pH difference between the fluids that are in contact with the bipolar membrane on different sides thereof achieves an electric current. In a presently preferred embodiment of the invention ions are transported to the salt solution to maintain electric neutrality.
In the energy (re)generation state generating energy preferably comprises water splitting that preferably takes place in the bipolar membrane. In the energy generation state, at the boundary or intermediate layer between the anion part and the cation part of the bipolar membrane, H20 is formed due to H+ arriving at this boundary through the cation part of the bipolar membrane and OH arriving at this boundary through the anion part of the bipolar membrane. H20 exits the bipolar membrane in preferably both directions to the adjacent compartments, preferably in equal amounts.
At the cathode, water splitting can be performed performing 4H20+4e ->2H2+40H , while at the anode, the anode reaction may involve 2H20-^4e"+02+4H+. These reactions take place in one of the possible embodiments according to the present invention. It will be understood that alternative reactions in the electrode compartments could also be envisaged in accordance with the invention.
Electrons run from the anode to the cathode via an external circuit thereby generating energy. The incoming fluids are diluted in the energy generation state. Energy is generated using the (ionic) concentration differences between the different fluids in the different compartments of the reactor.
In the energy generation state water is produced at the interface of the anion and cation parts of the bipolar membrane. The produced water exits the bipolar membrane on one of the sides thereof. Therefore, this water dilutes the solutions that are in contact with one of the side surfaces of the bipolar membrane. This influences the energy generation efficiency. In case the tendency of the produced water flow is more towards one of the two solutions that are in direct contact with one of the side surfaces of the bipolar membrane, the energy generation efficiency is negatively effected even more.
In accordance with the present invention the difference in water activity of both fluids in contact with the bipolar membrane is preferably minimized in at least the energy generation state. This has the effect that the water that is produced in the bipolar membrane is preferably equally distributed over the two fluids that are in contact with the bipolar membrane, thereby minimizing the diluting effect on the efficiency of the energy generation.
Bipolar membranes can be provided as single layer or single film membrane with one side surface being treated to act as anion exchange part and the other side surface being treated to act as cation exchange part. Also, bipolar membranes can be provided as laminated membranes, also referred to as multi-layer membranes. For example, the laminated bipolar membrane can be provided as a two layer membrane with an anion exchange layer and a cation exchange layer, or as a three layer membrane having an intermediate layer between the anion and cation exchange layers. In practice, when using laminated bipolar membranes, ballooning or delaminating of the laminated bipolar membrane may occur in case of an unequal water activity of the liquids in contact with the bipolar membrane. This significantly limits the applicability and/or efficiency of such bipolar membrane and any energy generating process using such laminated bipolar membrane.
As a further effect of minimizing the difference in water activity of the fluids on both sides of the bipolar membrane during the energy generation, the risk of ballooning or delaminating of the laminated bipolar membrane is significantly reduced. It is shown that a difference in water activity of both fluids in contact with the laminated bipolar membrane significantly contributes to the problems of ballooning and delaminating that have been experienced in conventional methods and/or systems.
According to the invention, providing fluids on both sides of the bipolar membrane with ion concentrations, according to the invention involving a pH difference between the fluids on both sides of the bipolar membrane, such that the difference in water activity of both fluids in contact with the bipolar membrane is minimized, prevents so-called ballooning and delaminating of the laminated bipolar membrane.
Therefore, the method according to the present invention enables the use of a bipolar membrane for regenerative storing and generating energy in a system having the same membrane configuration in both the energy storage state and the energy generation state, thereby achieving an effective regenerative energy storing and generating method using a single or multi-layer bipolar membrane. In fact, the energy generation can be performed efficiently due to keeping the difference in water activity of the fluids on both sides of the bipolar membrane minimal. In addition, maintaining the difference in water activity of both fluids in contact with the bipolar membrane minimal, provides a solution to the ballooning and delaminating problems that occur with laminated bipolar membranes and render conventional methods and systems ineffective.
As a further advantage, the method according to the present invention provides an energy storage and regeneration that is safer and more cost effective as compared to conventional approaches.
Furthermore, the method according to the invention can be applied in so-called stand-alone applications, in other words in off-grid applications, thereby also enabling effective energy storage in remote areas, for example.
The present invention can be applied advantageously, especially in relation to storing and (re)generating electrical energy originating from renewable energy sources, like solar energy, wind energy etc. The storage of such energy is possible with the increased energy density as compared to a method and/or system using a salt gradient in a RED process. The present invention enables higher energy densities, for example of factor 10-30 higher, as compared to salinity gradients that are based on diluted and concentrated salt solutions. For example, using diluted and concentrated salt solutions, energy density is about 0.5-1 kWh/m3.
Especially the use of a bipolar membrane that enables the combination of protons and hydroxide ions to water inside this membrane provides an effective means enabling increasing the energy density. For example, if the method according to the invention during application of an external current generates an amount of 22.2 Wh is stored in the volume of 1 liter of 1 molair acid solution and 1 liter of 1 molair base solution. This corresponds to 22.2 kWh/2m3, or 11.1 kWh/m3. For an average household to be able dealing with the day-night regime of energy supply and energy demand, typically an energy storage capacity in the range of 10-20 kWh would be required. In this example, this storage capacity can be achieved with a volume of 1 to 2 m3. It will be understood that in case of higher concentrations for the fluids being used, the required volume can be decreased even further.
Preferably, the system is operated in a temperature range of -20 to +100°C, more preferably in a temperature range of -10 to +80°C. The electrodes preferably have a sufficiently high electrical conductivity and catalytic activity towards water oxidation and water reduction. Possible materials include graphite, carbon, titanium coated with a (mixed) metal oxide like e.g. PtxIry, RuxIry, RuOx, TaxIry, and Ti coated with a noble metal like Pt.
In a presently preferred embodiment according to the present invention, in use, the reactor is provided with three fluids, the first fluid comprising a salt solution, the second fluid comprising an acid solution and a third fluid comprising a base solution.
The provision of three fluids provides an effective system to store and generate energy.
The acid and base solutions are provided on opposite sides of the bipolar membrane thereby defining a pH difference of both fluids in contact with the bipolar membrane. The salt fluid is provided in another compartment and is not in direct contact with the bipolar membrane.
In the energy generation state the cell unit in the reactor according to the present invention preferably comprises three chambers that are defined with a cation exchange membrane, an anion exchange membrane and a bipolar membrane. These membranes define the cell unit with the three compartments, thereby enabling providing three different fluids to the unit. In the energy generation state the fluids are provided, such that there is a pH difference between the fluids on both sides of the bipolar membrane and that are in direct contact with the bipolar membrane, while the difference in water activity of the fluids in contact with the bipolar membrane is kept to a minimum. Preferably, in the energy generation state water is formed at the intermediate layer between the cation and anion layers of the bipolar membrane.
Preferably, the salt solution comprises one or more of the following ions: Li+, Na+, K+, Mg2+, Ca2+, Ba2+, and Cl, F, Br, I , S042, N03, C104.
Furthermore, preferably the base solution comprises one or more of the following ions:
Li+, Na+ and K+, Mg2+, Ca2+, Ba2+, and OH .
Preferably, the acid solution comprises one or more of the following ions: H+, and F, Cl ,
Br , I , S042 , N03, C104 .
In a presently preferred embodiment according to the invention the method is applied using an acid solution comprising HC1, the base solution comprises LiOH and/or NaOH and/or KOH, and the salt solution comprises LiCl and/or NaCl and/or KC1.
In an alternative preferred embodiment according to the invention the method is applied using an acid solution comprising HN03, the base solution comprises LiOH and/or NaOH and/or KOH, and the salt solution comprises LiN03 and/or NaN03 and/or KN03.
In a presently preferred embodiment according to the invention the method is applied using a NaCl salt solution, NaOH base solution and HC1 acid solution. It is shown that a concentration of 0.5 mol/1 for these three fluids resulted in an effective method for regenerative storing and generating of energy. For the solution in the electrode compartments use is made of a fluid comprising 0.5 mol/1 Na2S04. It will be understood that other solutions for the electrodes could also be envisaged in accordance with the present invention.
In a presently preferred embodiment according to the invention the combination of NaCl and H20 for electrodialysis/energy storage and the combination of HC1 and NaOH for RED/energy generation is used. This provides an effective operation for storing and generating energy. Especially NaCl with NaOH and HC1, and Na2S04 for the electrode compartments, can be used effectively in the method according to the invention.
In a presently preferred embodiment according to the invention the difference in water activity of both fluids in contact with the bipolar membrane is maintained within the range of -0.015 to +0.015, and preferably in the range of -0.012 to +0.012, and most preferably in the range of-0.01 to +0.01.
Maintaining the difference in water activity of both fluids in contact with the bipolar membrane within these ranges improves the overall efficiency of the method and prevents ballooning and/or delaminating of the (laminated) bipolar membrane and limits the unequal transport of the generated water inside the bipolar membrane to both fluids in contact with the bipolar membrane.
In a presently preferred embodiment according to the present invention, the method further comprises the step of providing an additional electrolytic fluid and/or an organic compound to one or more of the fluids, such that water activity of such fluid is maintained.
Providing an additional electrolytic fluid providing a background electrolyte and/or an organic compound enables keeping water activity substantially equal at both sides of the bipolar membrane, while the pH difference between the liquids in contact with the bipolar membrane can be used to generate electrical energy. Such background electrolyte may comprise electrolyte, for example NaCl, KC1, KN03 having a concentration in the range of 0.1 to 3 mol/1. Preferably, all solutions are provided with such background electrolytic fluid to maintain a substantially equal water activity at both sides of the bipolar membrane. This provides an effective method for storing and generating electrical energy with the reactor maintaining its configuration during the different states of the method.
In a further preferred embodiment according to the present invention, the method further comprises the step of controlling the difference in water activity of both fluids in contact with the bipolar membrane.
When storing and/or generating electrical energy, the difference in water activity of both fluids in contact with the bipolar membrane may start to change due to changing concentrations, for example. By controlling the difference in water activity of both fluids in contact with the bipolar membrane within boundaries, preferably keeping this difference in water activity of both fluids in contact with the bipolar membrane to a minimum, problems with ballooning and/or delaminating of the (laminated) bipolar membrane can be prevented, and the overall efficiency of the method is improved.
In a presently preferred embodiment according to the present invention, the difference in water activity between both fluids in contact with the bipolar membrane can be controlled by controlling at least one of the fluids in contact with the bipolar membrane in relation to pump speed involving a pump controller.
By controlling pump speed the flow speed of the individual fluid(s) can be controlled effectively, thereby enabling manipulation of the difference in water activity of the fluids in contact with the bipolar membrane. As an alternative thereto, or in combination therewith, the amount of background electrolytic fluid that is supplied to one or more of the fluids can be controlled.
Controlling the difference in water activity difference between both fluids in contact with the bipolar membrane during operation improves the overall efficiency of the method and prevents the system reaching operating conditions that could result in ballooning and/or delaminating of the (laminated) bipolar membrane.
The invention further relates to a regenerative bipolar membrane fuel cell for storing and generating energy that is configured for performing the method as described above, with the cell comprising: a reactor with an anode compartment having an anode and a cathode compartment having a cathode; and a number of cell units separating the anode and cathode compartments, wherein the cell unit comprises an anion exchange membrane, a cation exchange membrane, and a bipolar membrane, wherein the membranes defining compartments.
The cell provides the same effects and advantages as those as described for the method.
More specifically, the cell enables storage of energy in an energy storage state as chemical energy at time periods of an energy surplus, and providing electrical energy in an energy generation state by converting these components in time periods of energy shortage. As the cell is configured to keep the difference in water activity between both fluids in contact with the bipolar membrane to a minimum, this provides an effective system to store energy that can be regenerated.
In a presently preferred embodiment according to the present invention, the cell unit comprises a hexagonal shape.
Providing a hexagonal cross-flow cell for the three chamber cell unit, an effective cell configuration is provided. The hexagonal shape for the cell unit particularly provides for minimal pressure drops at the inlet and/or outlet of the cell unit. This renders the configuration relatively effective as compared to conventional systems.
In a presently preferred embodiment, the fuel cell comprises a pump controller that is configured to control a pump speed based on the difference in water activity difference of the fluids in contact with the bipolar membrane. By manipulating pump speed, the difference in water activity of the fluids in contact with the bipolar membrane can be maintained at a minimum level, thereby improving the overall efficiency of the method, and preventing ballooning and/or delaminating of the (laminated) bipolar membrane. In addition thereto, or as an alternative there for, pump speed of electrolytic background fluids can be controlled.
Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:
Figure 1 shows a configuration of a reactor capable of performing the method according to the present invention;
Figure 2 shows an alternative configuration;
Figure 3A-E show the difference in water activity vs. molality of some solutions; Figures 4-7 show some experimental results; and
Figure 8 shows a hexagonal shape for the cell unit according to the present invention.
Regenerative bipolar membrane fuel cell 2 (Figure 1) comprises first electrode 4 and second electrode 6 in first electrode compartment 8 and second electrode compartment 10, respectively. It will be understood that another number and/or configurations of electrode could also be envisaged in accordance with the invention. Between electrodes 4, 6 a number of membranes are provided that separate electrode compartments 8, 10. In the illustrated embodiment, two cell units 12 are provided. Between second cell unit 12 and first electrode 4 cation exchange membrane 20 is provided.
Each cell unit 12 comprises anion exchange membrane 22 and cation exchange membrane 24 that are separated by bipolar membrane 26. Cell unit 12 defines three compartments 28, 30, 32. In use, first compartment 28 is provided with a salt solution, such as 0.5 mol/1 NaCl. In use, second chamber 30 is provided with an acid solution, such as 0.5 mol/1 acid solution HC1. In use, third compartment 32 is provided with a base solution, such as 0.5 mol/1 NaOH.
Electrodes 4, 6 are connected via circuit 34. In the illustrated embodiment, system 2 is shown in the electrical energy generating state wherein a circuit 34 comprises load 36.
Furthermore, circuit 34 comprises switch 38 for switching on and off the electrical energy generation of system 2. Electrodes 4, 6 are made of titanium mesh, e.g. with a mixed metal oxide coating like PtxIry, RuxIry, TaxIry.
Experiments performed with a system according to system 2 with ten cell units 12 that are placed in series between electrodes 4, 6, having (additional) cation exchange membrane 20 and one of cation exchange membranes 16 of cell unit 12 as end membranes. The solution for the electrode compartments 8, 10 that was used in the experiments was 0.5 mol/1 Na2S04. Salt solution for the three chamber cell unit 12 was 0.5 mol/1 NaCl, base solution was 0.5 mol/1 NaOH, and acid solution was 0.5 mol/1 HC1. Results with this configuration will be described later.
In the illustrated embodiment system 2 comprises separate pumps 40, 42, 44 for the three specific fluids. It will be understood that also separate pumps can be provided for each individual compartment to enhance control possibilities. In the illustrated embodiment, fluids are stored in containers 46, 48, 50, 52, 54, 56. It will be understood that another configuration and/or number of containers can be provided in accordance with the invention. For illustrative reasons only, the containers for the fluids leaving system 2 are not shown in the figures.
System 58 (Figure 2) comprises electrodes 4, 6 and cell unit 12 to illustrate the principle of electrical energy generation. In the illustrated embodiment, electrode reactions at electrodes 4, 6 include at electrode 4 the reaction 4H20+4e -^2H2+40H and at second electrode 6 2H20-^4e +02+4H+. Electrode 4 acts as cathode and electrode 6 acts as anode, in the illustrated energy generating state of system 58. In the illustrated electrical energy generation, the concentrated NaOH and HC1 solutions are diluted while the NaCl fluid is concentrated in this state.
Optionally, background electrolytic fluid from container 60 (Figure 1) is provided by separate pumps 62, 64, 66 to the other three fluids. It will be understood that other configurations for the electrolytic fluid with one or more additional containers 60 and/or a different number of pumps 62, 64, 66 could also be envisaged in accordance with the present invention.
For NaOH and HC1 solutions water activity difference is illustrated in Figure 3A vs. molality. For molalities up to two water activities for both solutions are about equal (see also Figure 3B). For higher molalities water activity difference start to increase significantly. In case the method according to the present invention is performed at higher molalities, water activities have to be chosen carefully. For example, water activity of NaOH with a molality of 6 is about equal to the water activity of HC1 with a molality of about 4.5. At these levels, the difference in water activity of both HC1 solution and NaOH solution in contact with the bipolar membrane can be kept to a minimum. This illustrates a possible approach to manipulate the difference in water activity difference of both fluids in contact with bipolar membrane 26. As an alternative, or in addition thereto, background electrolyte fluids can be used to reduce the difference in water activity of fluids in contact with the bipolar membrane.
Water activity (Figure 3C) is shown vs. molality of suphuric acid (□), FiOH (0), NaOH (A) and KOH (o) with closest fits shown for the solutions. Depending on the molality of a fluid the corresponding water activities of other fluids can be shown depending on the molality. It will be understood that other solutions also show similar water activities in relation to molality, thereby enabling manipulation of the difference in water activity of both fluids in contact with bipolar membrane 26.
Figure 3D shows water activity difference versus molality for HC1 versus FiOH (0), HC1 versus NaOH (□), and HC1 versus KOH (A) with their closest fits. Also shown is a range for water activity differences of 0.01. Highest possible molality for the illustrated water activity range is achieved with a system with KC1 leading to HC1 and KOH. Figure 3E shows water activity difference versus molality for HN03 versus FiOH (0), NaOH (□) and KOH (A), together with their closest fits and a water activity range of 0.01. It is shown that the system with NaN03 leading to NaOH and HN03 has the smallest difference in water activity of both fluids, comprised of NaOH and HN03 solutions with equal molality, in contact with bipolar membrane 26, and is capable of operating at the highest molality thereby improving the overall efficiency of the method, and preventing ballooning and/or delaminating of (laminated) bipolar membrane 26.
The results show several combinations that can be used in a method and/or system according to the present invention, such as KN03 and preferably NaN03. It will be understood hat also other solutions could be used in accordance with the present invention.
The aforementioned experiment is performed with a ten cell unit system, wherein an effective area of 100 cm2 for each membrane is used. Results are shown in Figures 4-7. The maximum power that is obtained was about 0.65 Watt. The effective electrode area was about 100 cm2. The total installed membrane area was about 3.000 cm2. The tests were being performed at room temperature. Figure 4 shows the power vs. discharge current. Figure 5 shows power density (Watt/m2) vs. discharge current density (A/m2), wherein the total installed membrane area was used to calculate the power density and the electrode area is used to calculate the current density. In the experiment, electrode reactions comprised a water oxidation reaction to oxygen gas and a water reduction reaction to hydrogen gas. This resulted in relatively high voltage losses at the electrodes in relation to the limited number of membrane units that are placed in series between the electrodes. By increasing the number of cell units 12 between electrodes 4, 6, these losses can be minimized.
Figure 6 illustrates the stack voltage vs. discharge current, showing a slope of the curve of about 12.9 Ohm. Stack voltage is lowered with the losses that occur at the electrodes where water oxidation and water reduction reactions take place. The slope of the curve can be decreased by increasing the number of membranes between the electrodes, since this reduces the influence of the relative voltage losses at the electrodes. The resistance distribution was calculated from the membrane resistances (Ralex) anion and cation exchange membranes and Fumatech bipolar membrane. Figure 7 illustrates the resistance distribution of the ten membrane unit stack with a cation exchange membrane (CEM), bipolar membrane (BPM) and anion exchange membrane (AEM) per cell unit 12, and the solutions and electrodes 4, 6.
The experiment illustrates the applicability of the method for storing and (re)generation of electrical energy according to the present invention.
In an alternative embodiment, stack 68 of cell units 12 (Figure 8) is provided with hexagonal shape 70. Stack 68 has inlet 72 and outlet 74 for the salt solution, inlet 76 and outlet 78 for the acid solution, and inlet 80 and outlet 82 for the base solution. Hexagonal shape 70 defines an active region 84 for stack 68. Hexagonal shape 70 reduces pressure losses at inlets and outlets of stack 68.
The present invention is by no means limited to the above described preferred embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged.
Clauses 1. Method for operating a regenerative bipolar membrane fuel cell, comprising the steps of: providing a regenerative bipolar membrane fuel cell comprising: a reactor with an anode compartment having an anode and a cathode compartment having a cathode; and a number of cell units separating the anode and cathode compartments, wherein the cell unit comprises an anion exchange membrane, a cation exchange membrane, and a bipolar membrane, with the membranes defining compartments; providing a number of fluids to the cell, with at least a fluid on both sides of the bipolar membrane with ion concentrations such that the difference in water activity of the fluids on both sides of the bipolar membrane is minimized; storing energy in an energy storage state by providing an external current to the reactor such that a pH difference between fluids in contact with the bipolar membrane is achieved; switching between the energy storage state and an energy generation state; and regenerating energy in the energy generating state from the pH difference between fluids in contact with the bipolar membrane. 2. Method according to clause 1, wherein the difference in water activity of the fluids on both sides of the bipolar membrane is minimized in the energy generation state. 3. Method according to clause 1 or 2, wherein storing energy comprises water splitting. 4. Method according to clause 3, wherein the water splitting is performed in the bipolar membrane. 5. Method according to one or more of the foregoing clauses, wherein in use the reactor is provided with three fluids, wherein a first fluid comprising a salt solution, a second fluid comprising an acid solution, and a third fluid comprising a base solution. 6. Method according to clause 5, wherein the salt solution comprises one or more of the following ions: Li+, Na+, K+, Mg2+, Ca2+, Ba2+, and Cl, F, Br, I, S042, N03, C104. 7. Method according to clause 5 or 6, wherein the base solution comprises one or more of the following ions: Li+, Na+, K+, Mg2+, Ca2+, Ba2+, and OH . 8. Method according to clause 5, 6 or 7, wherein the acid solution comprises one or more of the following ions: H+, and F , Cl , Br', I , SO42 , N03, CIO4. 9. Method according to one or more of the clauses 5-8, wherein the acid solution comprises HC1, the base solution comprises LiOH and/orNaOH and/or KOH, and the salt solution comprises LiCl and/or NaCl and/or KC1. 10. Method according to one or more of the clauses 5-9, wherein the acid solution comprises HNO3, the base solution comprises LiOH and/or NaOH and/or KOH, and the salt solution comprises LiN03 and/or NaN03 and/or KN03. 11. Method according to one or more of the foregoing clauses, wherein the difference in water activity of both fluids in contact with the bipolar membrane is maintained within the range of -0.015 to +0.015, and preferably in the range of -0.012 to +0.012, and most preferably in the range of -0.01 to +0.01. 12. Method according to one or more of the foregoing clauses, further comprising the step of supplying an additional electrolytic fluid and/or an organic compound, such that water activity of such fluid is maintained. 13. Method according to one or more of the foregoing clauses, further comprising the step of controlling the difference in water activity of both fluids in contact with the bipolar membrane. 14. Method according to clause 13, wherein controlling the difference in water activity of both fluids in contact with the bipolar membrane comprises controlling pump speed for one or more of the fluids with a pump controller. 15. Regenerative bipolar membrane fuel cell for storing and generating energy that is configured for performing the method according to one or more of the foregoing clauses, the cell comprising: a reactor with an anode compartment having an anode and a cathode compartment having a cathode; and a number of cell units separating the anode and cathode compartments, wherein the cell unit comprises an anion exchange membrane, a cation exchange membrane, and a bipolar membrane, the membranes defining compartments. 16. Cell according to clause 15, wherein the cell unit comprises a hexagonal cell shape. 17. Cell according to clause 15 or 16, further comprising a pump controller configured for control of pump speed based on the difference in water activity of both fluids in contact with the bipolar membrane.

Claims (17)

1. Werkwijze voor het bedrijven van een regeneratief bipolair membraan brandstofcel, omvattende de stappen: het voorzien van een regeneratief bipolair membraan brandstofcel omvattende: een reactor met een anodecompartiment met een anode en een cathodecompartiment met een cathode; en een aantal celeenheden welke de anode en cathodecompartimenten scheiden, waarin de celeenheid omvattende een anionuitwisselingsmembraan, een kationuitwisselingsmembraan, en een bipolair membraan welke compartimenten definiëren; het voorzien van een fluïdum aan beide zijden van het bipolair membraan met ionconcentraties zodanig dat het verschil in wateractiviteit tussen de fluïda aan beide zijden van het bipolair membraan minimaal is; het opslaan van energie in een energie-opslagtoestand door het voorzien van een externe stroom aan de reactor, zodanig dat een pH verschil tussen fluïda in contact met het bipolaire membraan wordt bewerkstelligd; het schakelen tussen de energie-opslagtoestand en een energiegeneratietoestand; en het generen van energie in de energiegeneratietoestand uit het pH verschil tussen de fluïda in contact met het bipolaire membraan.A method for operating a regenerative bipolar membrane fuel cell, comprising the steps of: providing a regenerative bipolar membrane fuel cell comprising: a reactor with an anode compartment with an anode and a cathode compartment with a cathode; and a plurality of cell units separating the anode and cathode compartments, wherein the cell unit comprising an anion exchange membrane, a cation exchange membrane, and a bipolar membrane defining compartments; providing a fluid on both sides of the bipolar membrane with ion concentrations such that the difference in water activity between the fluids on both sides of the bipolar membrane is minimal; storing energy in an energy storage state by providing an external current to the reactor such that a pH difference between fluids in contact with the bipolar membrane is achieved; switching between the energy storage state and an energy generation state; and generating energy in the energy generation state from the pH difference between the fluids in contact with the bipolar membrane. 2. Werkwijze volgens conclusie 1, waarin het verschil in wateractiviteit van beide fluïda in contact met het bipolaire membraan wordt geminimaliseerd in de energiegeneratietoestand.The method of claim 1, wherein the difference in water activity of both fluids in contact with the bipolar membrane is minimized in the energy generation state. 3. Werkwijze volgens conclusie 1 of 2, waarin het opslaan van energie watersplitsing omvat.The method of claim 1 or 2, wherein storing energy comprises water splitting. 4. Werkwijze volgens conclusie 3, waarin de watersplitsing wordt uitgevoerd in het bipolaire membraan.The method of claim 3, wherein the water cleavage is performed in the bipolar membrane. 5. Werkwijze volgens één of meer van de voorgaande conclusies, waarin in gebruik de reactor wordt voorzien van drie fluïda, een eerste fluïdum omvattende een zoutoplossing, een tweede fluïdum omvattende zuuroplossing, en een derde fluïdum omvattende een basische oplossing.A method according to any one of the preceding claims, wherein in use the reactor is provided with three fluids, a first fluid comprising a saline solution, a second fluid comprising an acid solution, and a third fluid comprising a basic solution. 6. Werkwijze volgens conclusie 5, waarin de zoutconcentratie omvattende één of meer van de volgende ionen: Li+, Na+, K+, Mg2+, Ca2+, Ba2+, en Cl , F, Br', I , S042, N03, C104.The method of claim 5, wherein the salt concentration comprising one or more of the following ions: Li +, Na +, K +, Mg 2+, Ca 2+, Ba 2+, and Cl, F, Br ', I, SO 2 042, NO 3, C 10 7. Werkwijze volgens conclusie 5 of 6, waarin de basische oplossing omvattende één of meer van de volgende ionen: Li+, Na+ en K+, Mg2+, Ca2+, Ba2+, en OH.The method of claim 5 or 6, wherein the basic solution comprising one or more of the following ions: Li +, Na + and K +, Mg 2+, Ca 2+, Ba 2+, and OH. 8. Werkwijze volgens conclusie 5, 6 of 7, waarin de zuuroplossing omvattende één of meer van de volgende ionen: H+, en F, Cl , Br", I , S042, N03, C104.A method according to claim 5, 6 or 7, wherein the acid solution comprising one or more of the following ions: H +, and F, Cl, Br ", I, SO42, NO3, C104. 9. Werkwijze volgens één of meer van de conclusies 5-9, waarin de zuuroplossing omvattende HC1, de base oplossing omvattende LiOH en/of NaOH en/of KOH, en de zoutoplossing omvattende LiCl en/of NaCl and/or KC1.A method according to any one of claims 5-9, wherein the acid solution comprising HCl, the base solution comprising LiOH and / or NaOH and / or KOH, and the saline solution comprising LiCl and / or NaCl and / or KCl. 10. Werkwijze volgens één of meer van de conclusies 5-9, waarin de zuuroplossing omvattende HN03, de base oplossing omvattende LiOH en/of NaOH en/of KOH, en de zout oplossing omvattende LiN03 en/of NaN03 en/of KN03.A method according to any one of claims 5-9, wherein the acid solution comprising HNO 3, the base solution comprising LiOH and / or NaOH and / or KOH, and the salt solution comprising LiNO 3 and / or NaNO 3 and / or KNO 3. 11. Werkwijze volgens één of meer van de voorgaande conclusies, waarin het verschil in water activiteit van beide fluïda in contact met het bipolaire membraan wordt gehouden in het bereik van -0.015 to +0.015, en bij voorkeur in het bereik van -0.012 tot +0.012, en met de meeste voorkeur in het bereik van -0.01 tot +0.01.A method according to any one of the preceding claims, wherein the difference in water activity of both fluids is kept in contact with the bipolar membrane in the range of -0.015 to +0.015, and preferably in the range of -0.012 to + 0.012, and most preferably in the range of -0.01 to +0.01. 12. Werkwijze volgens één of meer van de voorgaande conclusies, verder omvattende de stap van het toevoeren van additioneel elektrolytisch fluïdum en/of organische verbinding naar één of meer van de fluïda, zodanig dat wateractiviteit van een dergelijk fluïdum wordt gecontroleerd.Method according to one or more of the preceding claims, further comprising the step of supplying additional electrolytic fluid and / or organic compound to one or more of the fluids, such that water activity of such a fluid is controlled. 13. Werkwijze volgens één of meer van de voorgaande conclusies, verder omvattende de stap van het beheersen van het verschil in wateractiviteit van de fluïda in contact met het bipolaire membraan.The method of any one of the preceding claims, further comprising the step of controlling the difference in water activity of the fluids in contact with the bipolar membrane. 14. Werkwijze volgens conclusie 13, waarin het beheersen van het verschil in wateractiviteit van de fluïda in contact met het bipolaire membraan het aansturen van de pompsnelheid van één of meer van de fluïda met een pompregelaar omvat.The method of claim 13, wherein controlling the difference in water activity of the fluids in contact with the bipolar membrane comprises controlling the pumping speed of one or more of the fluids with a pump controller. 15. Regeneratief bipolair membraanbrandstofcel voor het opslaan en genereren van energie, welke is geconfigureerd voor het uitvoeren van de werkwijze volgens één of meer van de voorgaande conclusies, waarin de cel omvattende: een reactor met een anodecompartiment met een anode en een cathodecompartiment met een cathode; en een aantal celeenheden welke de anode en cathodecompartimenten scheiden, waarin de celeenheid omvattende een anion uitwisselingsmembraan, een kationuitwisselingsmembraan en een bipolair membraan definiërend compartimenten.A regenerative bipolar membrane fuel cell for storing and generating energy, which is configured to perform the method according to one or more of the preceding claims, wherein the cell comprising: a reactor with an anode compartment with an anode and a cathode compartment with a cathode ; and a plurality of cell units separating the anode and cathode compartments, wherein the cell unit comprising an anion exchange membrane, a cation exchange membrane and a bipolar membrane defining compartments. 16. Cel volgens conclusie 15, waarin de celeenheid een hexagonale vorm omvat.The cell of claim 15, wherein the cell unit comprises a hexagonal shape. 17. Cel volgens conclusie 15 of 16, verder omvattende een pompregelaar geconfigureerd voor het regelen van pompsnelheid gebaseerd op het verschil in wateractiviteit van de fluïda in contact met het bipolaire membraan.The cell of claim 15 or 16, further comprising a pump controller configured to control pump speed based on the difference in water activity of the fluids in contact with the bipolar membrane.
NL2014541A 2015-03-27 2015-03-27 Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for. NL2014541B1 (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
NL2014541A NL2014541B1 (en) 2015-03-27 2015-03-27 Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for.
PCT/NL2016/050207 WO2016159761A1 (en) 2015-03-27 2016-03-24 Method for operating of a regenerative bipolar membane fuel cell, and regenerative bipolar membrane fuel cell there for.
DK16727238.4T DK3274078T3 (en) 2015-03-27 2016-03-24 Method of using a regenerating bipolar membrane fuel cell and regenerating bipolar membrane fuel cell thereto
KR1020177030313A KR102526924B1 (en) 2015-03-27 2016-03-24 Operating method of regenerative bipolar membrane fuel cell and regenerative bipolar membrane fuel cell for the same
US15/556,887 US10541439B2 (en) 2015-03-27 2016-03-24 Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for
EP16727238.4A EP3274078B1 (en) 2015-03-27 2016-03-24 Method for operating of a regenerative bipolar membane fuel cell, and regenerative bipolar membrane fuel cell there for.
ES16727238T ES2738413T3 (en) 2015-03-27 2016-03-24 Method of operation of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell for the same
CN201680019106.3A CN107873111B (en) 2015-03-27 2016-03-24 Operation method of renewable bipolar membrane fuel cell and renewable bipolar membrane fuel cell thereof
HK18108463.1A HK1248923A1 (en) 2015-03-27 2018-06-29 Method for operating of a regenerative bipolar membane fuel cell, and regenerative bipolar membrane fuel cell there for

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL2014541A NL2014541B1 (en) 2015-03-27 2015-03-27 Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for.

Publications (2)

Publication Number Publication Date
NL2014541A NL2014541A (en) 2016-10-10
NL2014541B1 true NL2014541B1 (en) 2017-01-06

Family

ID=53189125

Family Applications (1)

Application Number Title Priority Date Filing Date
NL2014541A NL2014541B1 (en) 2015-03-27 2015-03-27 Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for.

Country Status (9)

Country Link
US (1) US10541439B2 (en)
EP (1) EP3274078B1 (en)
KR (1) KR102526924B1 (en)
CN (1) CN107873111B (en)
DK (1) DK3274078T3 (en)
ES (1) ES2738413T3 (en)
HK (1) HK1248923A1 (en)
NL (1) NL2014541B1 (en)
WO (1) WO2016159761A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11374242B2 (en) 2019-04-06 2022-06-28 Mark Minto Methods and apparatus for decoupling reactant activation and reaction completion
KR102361075B1 (en) * 2020-05-27 2022-02-11 연세대학교 산학협력단 Energy Harvesting Device
CN113659872A (en) * 2021-07-05 2021-11-16 合肥工业大学 Power generation device based on bipolar membrane and power generation method thereof

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4311771A (en) * 1978-12-21 1982-01-19 Allied Chemical Corporation Process for production of electrical energy from the neutralization of acid and base in a bipolar membrane cell
US6833205B2 (en) * 2000-07-20 2004-12-21 Proton Energy Systems, Inc. Electrochemical cell system output control method and apparatus
US7282294B2 (en) 2004-07-02 2007-10-16 General Electric Company Hydrogen storage-based rechargeable fuel cell system and method
NL1031148C2 (en) 2006-02-14 2007-08-16 Redstack B V Apparatus for performing a reverse electrodialysis process and method for performing a reverse electrodialysis process.
CN103270636A (en) 2010-11-03 2013-08-28 西门子私人有限公司 Electrodialysis systems and methods for energy generation and waste treatment

Also Published As

Publication number Publication date
EP3274078B1 (en) 2019-05-08
HK1248923A1 (en) 2018-10-19
WO2016159761A1 (en) 2016-10-06
EP3274078A1 (en) 2018-01-31
US20180198151A1 (en) 2018-07-12
KR102526924B1 (en) 2023-04-27
US10541439B2 (en) 2020-01-21
DK3274078T3 (en) 2019-08-05
NL2014541A (en) 2016-10-10
ES2738413T3 (en) 2020-01-22
CN107873111A (en) 2018-04-03
KR20170131531A (en) 2017-11-29
CN107873111B (en) 2020-11-20

Similar Documents

Publication Publication Date Title
Bebelis et al. Highlights during the development of electrochemical engineering
Forrestal et al. Sustainable desalination using a microbial capacitive desalination cell
CA2649873C (en) Method, apparatus and plant for desalinating saltwater using concentration difference energy
BR102019002402A2 (en) ELECTROCHEMICAL LIQUID DESICCANT REGENERATION SYSTEM
US20150086813A1 (en) Reverse electrodialysis energy generating system using capacitive electrodes and method there for
US4352864A (en) Metal/acid ion permeable membrane fuel cell
Bhat et al. An electrochemical neutralization cell for spontaneous water desalination
NL2014541B1 (en) Method for operating of a regenerative bipolar membrane fuel cell, and regenerative bipolar membrane fuel cell there for.
JP5192004B2 (en) How to stop water electrolysis system
CN112840492A (en) Cost-effective high energy density redox flow battery
US10604426B2 (en) High efficiency electrochemical desalination system that incorporates participating electrodes
WO2014164352A1 (en) Energy generation and storage using electro-separation methods and devices
Atlas et al. Theory of simultaneous desalination and electricity generation via an electrodialysis cell driven by spontaneous redox reactions
AU2016203645B2 (en) Redox desalination system for clean water production and energy storage
KR102015064B1 (en) Power generation system having serially connected heterogeneous reverse electrodialysis
JP5824122B1 (en) Liquid activation / electrolysis apparatus and liquid activation / electrolysis method
US11739433B2 (en) Method for removing non-proton cationic impurities from an electrochemical cell and an electrochemical cell
US20230097875A1 (en) Ferric ion reduction system to enable electrolyte rebalance within an iron flow battery
US20230387431A1 (en) Filtration applications in a redox flow battery
Khodadousti et al. Batteries in desalination: A review of emerging electrochemical desalination technologies
Cuesta et al. Desalination of sea water to potable levels without external energy input by electrochemical acid-base neutralisation
Erkmen Effect of residual gases in the electrodialysis cell on mass transfer
NL2015321B1 (en) Method for generating electricity with a Reversed Electro Dialysis (RED) process, and a stack, apparatus, and filler there for.
KR20120051944A (en) Manufacturing equipment of electrolyte for redox flow battery and manufacturing method thereof

Legal Events

Date Code Title Description
MM Lapsed because of non-payment of the annual fee

Effective date: 20200401